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Reduced risk of coronary artery disease is more closely linked to the function of HDL, the so-called "good cholesterol ", and not so much to its level in the blood as previously thought,according to a new US study published in the New England Journal of Medicine, NEJM . The discovery could affect the development of drugs that target HDLin treating heart disease , said the researchers. You can read about the study, led by the University of PennsylvaniaSchool of Medicine (Penn) in Philadelphia, online in the 13 Januaryissue of NEJM . A major cause of cardiovascular disease is atherosclerosis, causedby the build up of plaques of fatty materials like cholesterol onthe linings of artery walls. When researchers discovered that high levels of high-densitylipoprotein (HDL) cholesterol, the so-called "good" cholesterolwere linked to reduced risk of cardiovascular disease, there was arush to develop new drugs to treat heart disease by targeting HDLlevels. However, recent studies have questioned whether using drugs toincrease HDL is good for patients. In this study, Dr Daniel J Rader, director, Preventive Cardiologyat Penn, and colleagues, found that a particular measure of HDLfunction, which they call "efflux capacity", is more closely linkedto protection against heart disease than HDL level itself. Efflux capacity is a measure of how well HDL removes cholesterolfrom cholesterol-loaded macrophages, a type of white blood cell,that accumulate in arterial plaque. Recent studies have suggested that perhaps it is how HDL functionsrather than how much of it there is in the blood that affectscardiovascular risk and the effectiveness of HDL-targeted drugs, soRader and colleagues decided to investigate efflux capacity. "Our study is the first to relate a measure of HDL function - itsability to remove cholesterol from macrophages - to measures ofcardiovascular disease in a large number of people," Rader told thepress. For the study, 203 healthy people volunteered to undergo assessmentof the thickness of the "intima-media" of their carotid artery, ameasure of atherosclerosis. The researchers also recruited 442patients with coronary artery disease, and 351 patients without thedisease. To measure the efflux capacity of HDL in all three groups ofparticipants, Rader and colleagues used "a validated ex vivo systemthat involved incubation of macrophages with apolipoproteinB-depleted serum," taken from their blood samples. The results showed an inverse relationships between cholesterolefflux capacity and the thickness of the carotid intima-media bothbefore and after adjustment for HDL cholesterol levels. After adjusting for age and gender, the results also showed thatincreasing efflux capacity was tied to decreased likelihood ofhaving coronary artery disease. The strength of the link did notchange after adding traditional risk factors such as HDLcholesterol levels. The researchers also found that men and current smokers haddecreased HDL efflux capacity. Rader and colleagues suggested that although cholesterol efflux isonly one of the many functions of HDL, and represents only a smallfraction of the overall flow through the cholesterol pathway, it isprobably the one with most impact on protecting against heartdisease. Rader said their findings support the idea that measuring what HDLdoes gives better information than just measuring its level, andpoints to the need to measure HDL function in assessing new drugsthat target HDL. "Future studies may prove fruitful in elucidating additional HDLcomponents that determine cholesterol efflux capacity," he said. "Cholesterol Efflux Capacity, High-Density Lipoprotein Function,and Atherosclerosis." Amit V. Khera, Marina Cuchel, Margarita de la Llera-Moya, AmrithRodrigues, Megan F. Burke, Kashif Jafri, Benjamin C. French, JulieA. Phillips, Megan L. Mucksavage, Robert L. Wilensky, Emile R.Mohler, George H. Rothblat, and Daniel J. Rader. N Engl J Med , 2011; 364:127-135, online 13 January 2011. DOI: 10.1056/NEJMoa1001689 Additional source: University of Pennsylvania School of Medicine(press release, 12 Jan 2011). Written by: Catharine Paddock, PhD Copyright: Medical News Today Not to be reproduced without permission of Medical News Today Additional References Citations. I am an expert from glass-handicrafts.com, while we provides the quality product, such as China Hand Blown Glass Goblets , Handmade Glass Pendants, Hand Blown Glass Goblets,and more.
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